Laminar flow diffuser with integrated lighting

ABSTRACT

A laminar flow diffuser with integrated lighting has a frame for supporting an air plenum and a lower housing. The air plenum receives conditioned air from a source of conditioned air. The lower housing is attached to the bottom of the plenum. An aperture plate damper installed below the top plenum regulates the flow of air from the plenum through the laminar flow diffuser. A clear or translucent the perforated diffuser face forms the outlet from the lower housing to the room below. LED strips are positioned around the inside periphery of the lower housing. A perforated reflector panel is position below the aperture plate damper and above the LED strips to spread the light from the LED strips across the perforated diffuser face.

CLAIM OF PRIORITY

The present application claims priority from provisional PatentApplication No. 62/335,251, filed on May 12, 2016, and is a continuationin part of non-provisional patent application Ser. No. 16/286,684, filedFeb. 27, 2019, which is a continuation of non-provisional patentapplication Ser. No. 15/594,114, filed May 12, 2017, both of Which arerelied upon and incorporated herein in their entirety by reference.

FIELD OF THE INVENTION

This invention relates to air diffusers and more particularly to alaminar flow diffuser with integrated lighting.

BACKGROUND OF THE INVENTION

Laminar flow diffusers are located in the ceiling of a room immediatelyabove a work area and deliver a controlled downward flow of conditionedsupply air with minimal entrainment of residual room air. The lowentrainment of residual room air results from the low initial facevelocity of the air delivered by the laminar flow diffuser. The uniformlow velocity downward projection of supply air through a diffuser face,combined with low-level exhaust or return air inlets, is ideal forindustrial clean rooms or hospital operating rooms. The boundary layerof the air mass in the room is the only place where any appreciableentrainment of residual room air may occur. With the boundary layer,remote from the work area, the low velocity, controlled air massdelivered from the laminar flow diffuser effectively isolates the workarea from any effects or contaminants of the residual room air.

Laminar flow diffusers typically have a full flow butterfly styledampers to control the amount of air delivered downwardly through thediffuser face to the room below. The laminar flow diffusers aretypically configured and sized for either ceiling surface mount or forceiling T-bar installation.

Because of the low flow of the laminar flow diffusers, a substantialportion of the ceiling may be occupied by the laminar flow diffusers.Such a construction creates a possible trade-off between the ceilingarea allocated to the laminar flow diffusers and the ceiling areaallocated to lighting fixtures. Such a trade-off becomes particularlyacute in work areas that require a high degree of illumination as wellas a low degree of contaminant entrainment, such as hospital operatingrooms or industrial clean rooms.

SUMMARY OF THE INVENTION

In order to address the issue of limited ceiling space for both laminarflow diffusers and lighting fixtures, the present invention is a laminarflow diffuser with integrated light emitting diodes (LED). The laminarflow diffuser of the present invention includes a frame that supports anenclosed air plenum and a lower housing. The air plenum receivesconditioned air from a source of conditioned air and includes a toppanel, side panels, end panels, and an open bottom. The lower housing,comprising housing side panels and housing end panels, is attached tothe bottom of the plenum. An aperture plate damper is installed belowthe air plenum to control air flow through the diffuser. A clear ortranslucent engineered, fire rated polymer perforated diffuser faceforms the outlet from the lower housing to the room below. Theperforated diffuser face is approximately ⅛ inch in thickness.

The LED lighting comprises integrated LED lighting strips that aremounted on the inside of the lower housing sides and lower housing endsand above the perforated diffuser face. The LED lighting is designedsuch that an equivalent amount of light is provided from the laminarflow diffuser, as would have been provided by separate lights anddiffusers.

In a first embodiment, a perforated acrylic light guide is used toequalize the light emitted through the perforated diffuser face of thelaminar flow diffuser. The light guide comprises a ⅜ inch clear acrylicsheet with a reflective metal sheet mounted on top of the light guidepolymer sheet. The reflective metal sheet reflects the light transmittedthrough the light guide downward toward the perforated diffuser face andprevents light from being emitted inefficiently from the top of thelight guide. The light guide is perforated to allow for necessary airflow to pass through the light guide, through the perforated diffuserface, and into the room below. The light guide is mounted adjacent tothe LED strips and in the same plane as the LED strips. The lightproduced by the LED strips passes within the clear acrylic sheet of thelight guide, and the light guide equalizes the light within the laminarflow diffuser before the light is emitted from the perforated diffuserface of the laminar flow diffuser. The light guide is positioneddirectly above, spaced from, and parallel to the diffuse face in orderto transfer the maximum amount of light from the LED strips to thetranslucent perforated diffuser face and to provide a high quality,equalized, and even light to be emitted from the perforated diffuserface of the laminar flow diffuser.

The invention includes individual laminar flow diffusers and largerintegrated assemblies of individual laminar flow diffusers. Theindividual laminar flow diffusers generally are dimensioned to fit thestandard T-bar ceiling installations, having nominal dimensions of 24inches×24 inches or 24 inches×48 inches.

In the larger integrated assemblies of individual laminar flowdiffusers, the conditioned air supplied from a source of conditioned airis shared amongst the several laminar flow diffusers that are eitherindividually connected to air ducts or interconnected with a common airplenum. The air flow between the plenums for the individual laminar flowdiffusers is internally equalized due to the back pressure created bythe aperture plate damper within each laminar flow diffuser. Balancingthe air flow from each laminar flow diffuser is accomplished with theface adjustable aperture plates installed in each laminar flow diffuser.

As a result of the integrated lighting in the laminar flow diffuser, thelighting and the air distribution by the laminar flow diffusers areintegrated into the same ceiling space thereby saving ceiling space inoperating rooms and clean rooms.

In a second embodiment of the present invention, a perforated reflectorpanel replaces the light guide. The perforated reflector panel ismounted in the lower housing above the peripherally mounted LED lightingstrips in order to reflect the light created by the LED lighting stripstoward the perforated diffuser face. The perforated reflector panelincludes angled sections that reflect the light originating from theperipheral LED lighting strips toward the center of the of the diffuserface. An aperture damper is mounted above the perforated reflectorpanel.

Further objects, features and advantages will become apparent uponconsideration of the following detailed description of the inventionwhen taken in conjunction with the drawings and the appended claims.

BRIEF DESCRIPTION OF' THE DRAWINGS

FIG. 1 is a side perspective view of a first embodiment of an individuallaminar flow diffuser with integrated lighting in accordance with thepresent invention.

FIG. 2 is a bottom plan view of the first embodiment of the individuallaminar flow diffuser with integrated lighting in accordance with thepresent invention.

FIG. 3A is an end elevation section view of the first embodiment of theindividual laminar flow diffuser with integrated lighting as seen alongline 3A-3A in accordance with the present invention.

FIG. 3B is an enlarged portion of the end elevation section view of FIG.3A of the first embodiment of the individual laminar flow diffuser withintegrated lighting in accordance with the present invention.

FIG. 4A is a side perspective view of the first embodiment of theindividual laminar flow diffuser with the perforated face plate removedto expose the light guide in accordance with the present invention.

FIG. 4B is a bottom plan view of the first embodiment of the individuallaminar flow diffuser with the perforated face plate removed to exposethe light guide in accordance with the present invention.

FIG. 4C is a bottom perspective view of the first embodiment of thelight guide and aperture plate damper in accordance with the presentinvention.

FIG. 4D is an enlarged edge view of the first embodiment of the lightguide and aperture plate damper in accordance with the presentinvention.

FIG. 4E is an enlarged bottom plan view of the first embodiment of theindividual laminar flow diffuser with the perforated face plate removedto expose the light guide and aperture plate damper in accordance withthe present invention.

FIG. 5 is a perspective view of an integrated assembly of eightindividual laminar flow diffusers with integrated lighting in accordancewith the present invention.

FIG. 6 is a top plan view the integrated assembly of eight individuallaminar flow diffusers with integrated lighting in accordance with thepresent invention.

FIG. 7 is a room side perspective view of a second embodiment of alaminar flow diffuser with integrated lighting in accordance with thepresent invention.

FIG. 8 is an exploded room side perspective view of the secondembodiment of the laminar flow diffuser with integrated lighting inaccordance with the present invention.

FIG. 9 is a room side perspective view of the second embodiment of thelaminar flow diffuser with integrated lighting and with the diffuserface removed to reveal internal detail in accordance with the presentinvention.

FIG. 10 is an exploded room side perspective view of the secondembodiment of the laminar flow diffuser with integrated lighting andwith the diffuser face removed to reveal internal detail in accordancewith the present invention.

FIG. 11 is an exploded room side perspective view of the perforatedreflector panel and the aperture plate damper in accordance with thepresent invention.

FIG. 12 is a room side plan view (with a cutaway) of the secondembodiment of the laminar flow diffuser with integrated lighting inaccordance with the present invention.

FIG. 13A is side elevation section view of the second embodiment of thelaminar flow diffuser with integrated lighting in accordance with thepresent invention as seen along line 13A-13A of FIG. 12.

FIG. 13B is an end elevation section view of the second embodiment ofthe laminar flow diffuser with integrated lighting in accordance withthe present invention as seen along line 13B-13B of FIG. 12.

FIG. 14 is a room side perspective view of a third embodiment of aperforated reflector panel of the laminar flow diffuser with integratedlighting in accordance with the present invention.

FIG. 15 is a room side perspective view of fourth embodiment of aperforated reflector panel of a third embodiment of a laminar flowdiffuser with integrated lighting in accordance with the presentinvention.

FIG. 16 is a room side perspective view of the perforated reflectorpanel of the second embodiment of a laminar flow diffuser withintegrated lighting in accordance with the present invention,

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIGS. 1, 2, 3A-3B, and 4A-4E illustrate a first embodiment of anindividual laminar flow diffuser 10 of the present invention. Thelaminar flow diffuser 10 includes a frame 12 that supports a plenum 16and a lower housing 34. In other embodiments, the plenum 16 and thelower housing 34 may be a single structure divided into two sections.Such laminar flow diffusers 10 generally are dimensioned to fit thestandard T-bar ceiling installations and have nominal dimensions of 24inches×24 inches or 24 inches×48 inches. The laminar flow diffuser 10 ismounted in a T-bar ceiling of an occupied space by means of mountinghooks 14 attached to the frame 12.

The plenum 16 includes side panels 18, end panels 20, a top panel 22,and an open bottom. A conditioned air inlet 26 is formed in either oneof the end panels 20 or in the top panel 22. A HEPA filter (not shown)may be placed in the conditioned air inlet 26 to assure clean air isdelivered to the occupied room below the laminar flow diffuser 10. Thelower housing 34 is attached to the open bottom of the plenum 16. In oneembodiment the lower housing 34 has a peripheral panel comprisinghousing side panels 35 and housing end panels 36. The peripheral panel,however, may in other embodiments be a continuous panel or haveadditional panels. The plenum 16 and the lower housing 34 are separatedfrom each other by an aperture plate damper 38 that regulates the flowof air from the plenum 16 into the lower housing 34.

A clear or translucent engineered fire rated polymer perforated diffuserface 28 is connected to the bottom of the lower housing 34. The polymerperforated diffuser 28 face is made of ⅛″ thick polycarbonate andperforated with openings 30 to produce 13% to 23% free (open) area. Theperforated diffuser face 28 allows conditioned air to flow freely intothe room below with minimal pressure drop and allows for adequate flowequalization across the perforated face 28 thereby producing ideallaminar air flow characteristics in the room below. The translucentperforated diffuser face 28 is attached to the bottom of the frame 12 bymeans of quick release fasteners or threaded bolts 40 so that theperforated diffuser face 28 can be removed for maintenance and cleaning.While the illustrated diffuser has a flat rectangular perforateddiffuser face 28, the diffuser of the present invention is not limitedto such a flat rectangular perforated diffuser face and may incorporateother embodiments of diffuser outlets well known to those of ordinaryskill in the art.

A series of LED lighting strips 32 are attached to the inside of thehousing side panels 35 and housing end panels 36 of the lower housing 34by means of LED light strip mounts 33 (FIG. 3B). The LED lighting strips32 shine through the clear or translucent perforated diffuser face 28 toprovide light to the room below,

With reference to FIGS. 3A-3B and 4A-4E, a light guide 42 is used toequalize (spread) the light emitted from the LED lighting strips 32evenly across the area of the perforated diffuser face 28 of the laminarflow diffuser 10. The light guide 42 comprises a clear acrylic sheet 45with a reflective layer consisting of a metal sheet 44 mounted on top ofthe acrylic sheet 45. In other embodiments, the reflective layer may bea reflective coating used in place of the reflective metal sheet 44 toform the reflective layer. The light guide 42 has an edge 47.Particularly, the clear acrylic sheet 45 transmits maximum light alongits entire lower surface due to the 92% luminance transmittance rating.The light guide 42 is perforated with light guide openings 43 to allowfor 8% to 13% free (open) area to allow air flow to pass through thelight guide 42, in combination with the aperture plate damper 38 toprovide adequate back pressure for air flow equalization within thecommon plenum, and to minimize pressure drop. The reflective metal sheet44 reflects the light transmitted through the acrylic sheet 45 downwardtoward the perforated diffuser face 28 and prevents light from beingemitted inefficiently from the top of the acrylic sheet 45 away from thetranslucent perforated diffuser face 28

The light guide 42 is mounted on light guide mountings 49 and is spacedabove the perforated diffuser face to define an air space 48. The lightguide 42 is mounted with its edges 47 in close proximity to the LEDstrips 32, in the same plane as the LED strips 32, above the perforateddiffuser face 28, and parallel to the perforated diffuser face 28. Thelight produced by the LED strips 32 passes into the edges 47 of thelight guide acrylic sheet 45. The light guide 42 fully equalizes(spreads) the light within the laminar flow diffuser 10 before the lightis emitted from the perforated diffuser face 28 of the laminar flowdiffuser 10. As shown in FIG. 3B, the light guide 42 is positionedabove, and parallel to the perforated diffuse face 28, in order to allowthe maximum amount of light transfer from the LED strips 32 to the clearor translucent perforated diffuser face 28 and thereby provide a highquality, equalized and even light to be emitted from the laminar flowdiffuser 10. FIGS. 4A-4B show the light guide 42 mounted in the lowerhousing 34. FIG. 4D shows the edge 47 of the light guide 42, the acrylicsheet 45, the top mounted reflective metal sheet 44, the light guideopenings 43, and the aperture plate damper 38 positioned above thereflective sheet 44. FIG. 4E shows the light guide 42 backed by theaperture plate damper 38. As shown in FIG. 4E, the aperture plate damper38 with openings 41 can slide with respect to the light guide 42 (leftto right in FIG. 4E) so that the light guide openings 43 can beconstricted by the aperture plate damper 38 to thereby control the flowof conditioned air from the plenum 16 to the perforated diffuser face28.

FIGS. 5-6 illustrate an integrated assembly of eight individual laminarflow diffusers 10 a-10 h connected together. Such an integrated assemblycan provide a large well lighted work area where the amount of entrainedresidual room air is reduced. Each of the individual laminar flowdiffusers 10 a-10 h is supplied with conditioned air from a source ofconditioned air through top or side inlets 26 e-26 h (FIGS. 5 and 6).Where conditioned air is supplied to the inlets 26 e-26 h from a singleconditioned air source, the need to balance the air flowing through theindividual laminar flow diffusers may be required. The air flowing tothe plenums for the individual laminar flow diffusers is internallyequalized as a result of back pressure created by the light guide 42 andthe aperture plate damper 38 within each laminar flow diffuser 10 a-10h. Balancing the air flow from each laminar flow diffuser 10 a-10 h isaccomplished by means of the face adjustable aperture plate dampers 38installed in each laminar flow diffuser 10 a-10 h. Electrical power isprovided to each LED strip through a LED driver located in an electricalenclosure 24 on the top of the air plenum.

FIGS. 7-13B and 16 illustrate a second embodiment of an individuallaminar flow diffuser 110 of the present invention. The laminar flowdiffuser 110 includes a frame 112 that supports a plenum 116 and a lowerhousing 134. In other embodiments, the plenum 116 and the lower housing130 may be a single structure divided into two sections. Such laminarflow diffusers 110 generally are dimensioned to fit the standard T-barceiling installations and have nominal dimensions of 24 inches×24 inchesor 24 inches×48 inches. The laminar flow diffuser 110 is mounted in aT-bar ceiling of an occupied space by means of mounting hooks 114attached to the frame 112.

The plenum 116 includes side panels 118, end panels 120, a top panel122,and an open bottom. A conditioned air inlet 126 is formed in eitherone of the end panels 120 or in the top panel 122. A HEPA Filter (notshown) may be placed in the conditioned air inlet 126 to assure cleanair is delivered to the occupied room below the laminar flow diffuser110. The lower housing 134 is attached to the open bottom of the plenum116. In one embodiment the lower housing 134 has a peripheral panelcomprising housing side panels 135 and housing end panels 136. Theperipheral panel, however, may in other embodiments be a continuouspanel or have additional panels. The plenum 116 and the lower housing134 are separated from each other by an aperture plate damper 138 (FIG.11) that regulates the flow of air from the plenum 116 into the lowerhousing 134. The aperture plate damper 138 includes a fixed apertureplate 142 with fixed aperture slots 144 and a slidable aperture plate146 with slidable aperture slots 148. With reference to FIG. 13A, theslidable aperture plate 146 slides left and right below the fixedaperture plate 142 thereby opening the aperture plate damper 138 byaligning the fixed aperture plate slots 144 and the slidable apertureplate slots 148 and closing the aperture plate damper 138 by blockingthe fixed aperture plate slots 144 and the slidable aperture plate slots148. The amount of air passing through the aperture plate damper 138 canthus be regulated by positioning the slidable aperture plate 146 in anyposition between full open and full closed.

A clear or translucent engineered fire rated polymer perforated diffuserface 128 is connected to the bottom of the lower housing 134. Thepolymer perforated diffuser 128 face is made of ⅛″ thick polycarbonateand perforated with openings 130 to produce 13% to 23% free (open) area.The perforated diffuser face 128 allows conditioned air to flow freelyinto the room below with minimal pressure drop and allows for adequateflow equalization across the perforated face 128 thereby producing ideallaminar air flow characteristics in the room below. The translucentperforated diffuser face 128 is attached to the bottom of the frame 112by means of quick release fasteners or threaded bolts 129 so that theperforated diffuser face 128 can be removed for maintenance andcleaning. While the illustrated diffuser 110 has a flat rectangularperforated diffuser face 128, the diffuser of the present invention isnot limited to such a flat rectangular perforated diffuser face and mayincorporate other embodiments of diffuser outlets well known to those ofordinary skill in the art.

With reference to FIGS. 9, 10, 13A, and 13B, a series of LED lightingstrips 132 are attached to the inside of the lower housing side panels135 and lower housing end panels 136 of the lower housing 134. The LEDlighting strips 132 shine through the clear or translucent perforateddiffuser face 128 to provide light to the room below.

With reference to FIGS. 8-13B and 16, a perforated reflector panel 150is mounted below the aperture plate damper 138 and above the LEDlighting strips 132. The perforated reflector panel 150 has a reflectivelower surface 159 that reflects and equalizes (spreads) the lightemitted from the LED lighting strips 132 across the area of theperforated diffuser face 128 of the laminar flow diffuser 110. In theembodiment shown in FIGS. 8-13B and 16, the perforated reflector panel150 includes two flat portions 152 and a protruding reflector element161 comprising two angled portions 154 that meet to form atriangular-shaped ridge 156 extending along the length of the perforatedreflector panel 150. The reflective lower surfaces 159 of the two flatportions 152 and the two angle portions 154 reflect and scatter thelight from the LED lighting strips 132 across the perforated diffuserface 128. The spread of the light casts a more even light across thearea in the occupied space lighted by the laminar flow diffuser 110. Thereflective lower surface 159 of the perforated reflector panel 150 has alight reflectance value between 60 and 90 LRV.

The perforated reflector panel 150 has openings 158 for the passage ofair from the aperture plate damper 138 to the perforated diffuser face128. The perforated reflector panel 150 between 13% and 23% free (open)area.

In addition to the perforated reflector panel 150 (FIG. 16), otherconfigurations such as perforated reflector panel 250 (FIG. 15) andperforated reflector panel 350 (FIG. 14), likewise provide lightspreading to the perforated diffuser face 128. The perforated reflectorpanel 250, with openings 258, has flat portions 252 on either side of aprotruding reflector element 261 in the form of a half cylinder shapedsection 254 extending along the length of the perforated reflector panel250. The perforated reflector panel 350, with openings 358, has flatportions 352 on either side of a protruding reflector element 361 in theform of a pyramid-shaped section with sides 354 and a vertex 356. Theperforated reflector panels 250 and 350 have reflective lower surfaces259 and 359 respectively. Other protruding shapes may be adopted for theprotruding reflector elements, including without limit, a series oftriangular ridges, a series of half cylinder shapes, a series of pyramidshapes, a hemisphere shape, and a series of hemisphere shapes.

The reflective lower surfaces 259 and 359 have a light reflectance valuebetween 60 and 90 LRV. The perforated reflector panels 250 and 350 havebetween 13% and 23% free (open) area.

While this invention has been described with reference to preferredembodiments thereof, it is to be understood that variations andmodifications can be affected within the spirit and scope of theinvention as described herein and as described in the appended claims.

I claim:
 1. A diffuser with integrated lighting comprising: a. a framesupporting: i. an air plenum for receiving conditioned air from a sourceof conditioned air; and ii. a lower housing, having a peripheral panel,connected to the air plenum for receiving conditioned air from the airplenum; b. a damper mounted adjacent the air plenum to control the flowof conditioned air through the diffuser; c. a clear or translucentperforated diffuser face with openings, the perforated diffuser faceforming an outlet from the lower housing to an occupied space below thediffuser; d. at least one LED lighting strip attached to an insidesurface of the peripheral panel above the clear or translucentperforated diffuser face; and e. a perforated reflector panel mountedabove the LED lighting strips in the lower housing for distributinglight from the LED lighting strips evenly across the perforated diffuserface.
 2. The diffuser of claim 1, wherein the reflector panel includes aprotruding reflector element.
 3. The diffuser of claim 2, wherein theprotruding reflector element is an elongated V shape ridge.
 4. Thediffuser of claim 2, wherein the protruding reflector element is in theform of a pyramid shape.
 5. The diffuser of claim 2, wherein theprotruding reflector element is in the form of a half cylinder shape. 6.The diffuser of claim 2, wherein the protruding reflector element is inthe form of a hemisphere shape.
 7. The diffuser of claim 1, wherein theperforated reflector panel has a light reflectance value between 60 and90 LRV.
 8. The diffuser of claim 1, wherein the perforated reflectorpanel has free area between 13% and 23% free (open) area.